It's a fantastic idea, but Yeah, why did you use the name in French? Tolkien didn't hate the Arthurian matter. He regarded it as unsuitable as a mythology for England because it isn't English. In fact, the English are the bad guys, and the second option explicitly involves Christianity, which he regarded as fatal. After all, he wrote a long unfinished poem on Arthur. By the way, I have a website
https://www.thetolkienforum.com/wiki/Beleriand where I search for a lot of information about Argonath and the Kingdom of Gondor. Everything you want to know. I recommend it with all my pleasure.